The activities of RuBPC and C4 photosynthetic enzymes in ear and flag leaf blade were examined in wheat. The results showed that photosynthesis of ear was less sensitive to soil drought than that of flag leaf, and dec...The activities of RuBPC and C4 photosynthetic enzymes in ear and flag leaf blade were examined in wheat. The results showed that photosynthesis of ear was less sensitive to soil drought than that of flag leaf, and decrease of CO2 assimilation in flag leaf blade with water stress was more than that in ear. Compared with flag leaf, ear organs (awn, glume and lemma) had higher C4 enzyme activities and lower RuBPC activity. Under moderate water-stress, the increase of C4 enzyme activities was induced, and the increase was higher in ear than in flag leaf. Under severe water-stress, relatively higher C4 enzyme activities were still maintained in ear, rather than that in flag leaf. It suggests that high activities of C4 enzymes in ear may contribute to its high tolerance of photosynthesis to water-stress.展开更多
基金This work was supported by the State Key Basic Research and Development Plan(G1998010100)the State Natural Science Fund(30270780)the State"Tenth Five Year"Project(2001BA507A-09)of China
文摘The activities of RuBPC and C4 photosynthetic enzymes in ear and flag leaf blade were examined in wheat. The results showed that photosynthesis of ear was less sensitive to soil drought than that of flag leaf, and decrease of CO2 assimilation in flag leaf blade with water stress was more than that in ear. Compared with flag leaf, ear organs (awn, glume and lemma) had higher C4 enzyme activities and lower RuBPC activity. Under moderate water-stress, the increase of C4 enzyme activities was induced, and the increase was higher in ear than in flag leaf. Under severe water-stress, relatively higher C4 enzyme activities were still maintained in ear, rather than that in flag leaf. It suggests that high activities of C4 enzymes in ear may contribute to its high tolerance of photosynthesis to water-stress.